Otake S
Department of Radiology, Nagoya City University Medical School, Aichi, Japan.
AJR Am J Roentgenol. 1994 Feb;162(2):369-75. doi: 10.2214/ajr.162.2.8310929.
Muscular involvement of sarcoidosis is rare and occurs in two forms: nodular and myopathic. In the nodular variety, patients have single or multiple nodules in the skeletal muscles. Patients with the myopathic type have myalgia, muscle weakness, and atrophy. The purpose of this study was to determine the imaging features of these two types of muscular sarcoidosis and to compare the merits of different imaging procedures in establishing the diagnosis.
I retrospectivity reviewed the imaging findings of 28 patients with proved muscular sarcoidosis: 20 patients with the nodular type and eight with the myopathic type. Of the 20 patients with the nodular type, 20 had MR imaging, 17 had 67Ga scintigraphy, 10 had CT, six had sonography, and two had angiography. All eight patients with the myopathic type had MR imaging, and six of them had 67Ga scintigraphy.
In the nodular type of muscular sarcoidosis, the lesions were long and extended along muscle fibers. Axial MR images showed a star-shaped central structure of decreased signal intensity. Coronal and sagittal MR images showed three stripes, including an inner stripe of decreased signal intensity and outer stripes of increased signal intensity. After IV injection of gadopentetate dimeglumine, contrast-enhanced MR images showed enhancement in the peripheral area of the lesions of the nodular type. On sonograms, the central structure was hyperechoic and the peripheral area was hypoechoic relative to surrounding tissue. 67Ga scintigraphy showed increased uptake of radionuclide in the nodules. CT and angiography were of less diagnostic value. In the myopathic type, MR images showed no abnormalities. Myopathic involvement was visualized only with 67Ga scintigraphy, which showed diffusely increased uptake of radionuclide.
The unusual MR findings seen in the patients studied were suggestive of the nodular type of muscular sarcoidosis. 67Ga scintigraphy was useful for evaluating the whole body in patients with the nodular type and was the only imaging method that could show the myopathic type of involvement.
结节病的肌肉受累较为罕见，有结节型和肌病型两种形式。在结节型中，患者骨骼肌出现单个或多个结节。肌病型患者有肌痛、肌无力和肌肉萎缩。本研究的目的是确定这两种类型的肌肉结节病的影像学特征，并比较不同成像方法在确立诊断方面的优缺点。
我回顾性分析了28例经证实的肌肉结节病患者的影像学表现：20例为结节型，8例为肌病型。在20例结节型患者中，20例行磁共振成像（MR），17例行67镓闪烁扫描，10例行计算机断层扫描（CT），6例行超声检查，2例行血管造影。8例肌病型患者均行MR成像，其中6例行67镓闪烁扫描。
在结节型肌肉结节病中，病变呈长条状并沿肌纤维延伸。轴位MR图像显示信号强度减低的星状中心结构。冠状位和矢状位MR图像显示三条带，包括一条信号强度减低的内带和两条信号强度增加的外带。静脉注射钆喷酸葡胺后，增强MR图像显示结节型病变周边区域强化。超声检查显示，相对于周围组织，中心结构回声增强，周边区域回声减低。67镓闪烁扫描显示结节内放射性核素摄取增加。CT和血管造影的诊断价值较小。在肌病型中，MR图像未见异常。仅67镓闪烁扫描可显示肌病型受累，表现为放射性核素摄取弥漫性增加。
本研究中患者出现的不寻常MR表现提示为结节型肌肉结节病。67镓闪烁扫描有助于评估结节型患者的全身情况，是唯一能显示肌病型受累的成像方法。
